The Parthenon is constructed out of a combination of limestone and marble. The foundation of the building is limestone, while the columns are made of Pentelic marble, a kind of white, fine-grained marble quarried from the Penteli region in Greece.
Both marble and limestone are principally made up of calcite, a mineral containing calcium, carbon, and oxygen. When calcite sediment accumulates slowly over time, it becomes limestone; when limestone is subjected to extreme temperatures and pressures over large periods of time, it becomes marble. Pentelic marble is noted for its veins of pyrite and mica, which lend it a golden tinge. It was used by both the Greeks and Romans for architecture and sculptures. The Parthenon was the first time Pentilic marble was used to construct a building.